They are slightly shorter than original. I tried on on the Eight Ball, but it was too short and would not plunge the ball with enough power. I re installed the original, at it worked a treat. This concerns me a bit as I bought mine from BAA 5-6 years ago !

From the collar where the outer spring is mounted to the tip is 200mm. At the other end, the cavity for the clip is 30 mm from the tip. From memory, this is the area which is shorter.

I think these repros are all the same plunger, but just make sure it works when you install it.